Phase II jaw movements and masseter muscle activity during chewing in Papio anubis.
Phase II jaw movements and masseter muscle activity during chewing in Papio anubis.
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狒狒咀嚼过程中的第二阶段下颌运动和咬肌活动。
DOI：
10.1002/ajpa.20290
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发表时间：
2006
期刊：
影响因子：
--
通讯作者：
Hylander,WilliamL
中科院分区：
文献类型：
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作者：
Wall,ChristineE;Vinyard,ChristopherJ;Johnson,KirkR;Williams,SusanH;Hylander,WilliamL
据认为，灵长类动物的力量卒中有两个截然不同的咬合接触时期，每个时期都有下颌磨牙相对于上颌磨牙的特征运动。这两个运动被称为第一阶段和第二阶段，它们按顺序发生(Kay和Hiiemae[1974]是J.Phys。人类刑警组织。40：227-256，Kay和Hiiemae[1974]原猴生物学，匹兹堡：匹兹堡大学出版社，第501-530页)。第一阶段的运动据说与沿着一系列峰顶的剪切有关，产生平面的第一阶段小平面，并在磨牙盆地的表面上破碎。阶段I终止于中心咬合。第二阶段运动据说与沿着第一阶段结束时用于粉碎的相同表面的研磨有关([1987]Am J.Phys)。人类刑警组织。72：287-312；另见Hiiemae[1984]食品获取和处理，伦敦：学术出版社，第257-281页；Hylander和Crompton[1980]Am J.Phys。人类刑警组织。52：239-251，[1986]Arch.口头的。比奥尔。31：841-848)分析了猕猴的数据，并提出第二阶段的运动可能没有第一阶段的运动对食物分解的影响那么大，因为根据下颌骨应变模式的大小，内收肌和咬合力在离开正中咬合的过程中可能可以忽略不计。我们的目标是更好地在力量中风期间咀嚼运动学的更广泛的背景下理解第二阶段运动的功能意义。我们分析了Papio Anubis在I期和II期运动时下颌的垂直和横向运动以及咬肌和颞肌的相对活动。我们测试在第二阶段运动中是否有显著的肌肉活动，由此推断，咬合力是否发生。我们发现，在II期运动中，浅咬肌和深咬肌以及前、后颞肌的受力可以忽略不计。此外，与第一阶段相比，第二阶段的下颌运动较小。这些结果表明，第二阶段运动中的研磨对食物分解的重要性不大，第二阶段的大部分食物分解主要发生在第一阶段运动结束时(即第一阶段运动中的粉碎)。然而，我们注意到，根据第一阶段刻面的取向，在第一阶段期间，沿着第一阶段刻面也会发生显著的研磨。
It was proposed that the power stroke in primates has two distinct periods of occlusal contact, each with a characteristic motion of the mandibular molars relative to the maxillary molars. The two movements are called phase I and phase II, and they occur sequentially in that order (Kay and Hiiemae [1974] Am J. Phys. Anthropol. 40: 227–256, Kay and Hiiemae [1974] Prosimian Biology, Pittsburgh: University of Pittsburgh Press, p. 501–530). Phase I movement is said to be associated with shearing along a series of crests, producing planar phase I facets and crushing on surfaces on the basins of the molars. Phase I terminates in centric occlusion. Phase II movement is said to be associated with grinding along the same surfaces that were used for crushing at the termination of phase I. Hylander et al.([1987] Am J. Phys. Anthropol. 72: 287–312; see also Hiiemae [1984] Food Acquisition and Processing, London: Academic Press, p. 257–281; Hylander and Crompton [1980] Am J. Phys. Anthropol. 52: 239–251,[1986] Arch. Oral. Biol. 31: 841–848) analyzed data on macaques and suggested that phase II movement may not be nearly as significant for food breakdown as phase I movement simply because, based on the magnitude of mandibular bone strain patterns, adductor muscle and occlusal forces are likely negligible during movement out of centric occlusion. Our goal is to better understand the functional significance of phase II movement within the broader context of masticatory kinematics during the power stroke. We analyze vertical and transverse mandibular motion and relative activity of the masseter and temporalis muscles during phase I and II movements in Papio anubis. We test whether significant muscle activity and, by inference, occlusal force occurs during phase II movement. We find that during phase II movement, there is negligible force developed in the superficial and deep masseter and the anterior and posterior temporalis muscles. Furthermore, mandibular movements are small during phase II compared to phase I. These results suggest that grinding during phase II movement is of minimal importance for food breakdown, and that most food breakdown on phase II facets occurs primarily at the end of phase I movement (ie, crushing during phase I movement). We note, however, that depending on the orientation of phase I facets, significant grinding also occurs along phase I facets during phase I. Am J Phys Anthropol, 2006.© 2005 Wiley-Liss, Inc.